Genomic-based animal management in the early- and late-finishing system of Hanwoo cattle

In the Korean cattle feedlot industry, profitability is largely dependent on the carcass value at slaughter, which is influenced by genetic and environmental factors, including finishing time and feeding strategies. This study evaluated the predictive potential of genomic information for four economic traits-carcass weight (CWT), eye muscle area (EMA), backfat thickness (BFT), and marbling score (MS)-and the final meat grades in 975 Hanwoo cattle. Animals were grouped according to slaughter timing (Early and Late Finishing), and the genomic estimated breeding values for each trait were calculated. The analysis confirmed that all traits, except for CWT, were unaffected by finishing time. However, CWT was found to be influenced by both environmental factors and paternal effects. Trends in the phenotypic values for CWT, EMA, and MS increased with higher selection indices, while BFT exhibited mixed patterns, which suggests environmental influences. A-grade proportions increased with higher indices, thereby demonstrating the potential of genomic data for the early selection of high-grade animals. These findings underscore the value of genomic information in Hanwoo cattle breeding strategies, although sample size expansion may improve prediction accuracy for certain grades.